Dtc C1422 Master Cylinder Pressure Sensor Zero Point High Malfunction

Brake. Yaris. Ncp93, 131
Brake Control Dynamic Control Systems. Yaris. Ncp93, 131

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK STOP LIGHT OPERATION

READ VALUE USING TECHSTREAM (STOP LIGHT SWITCH)

CHECK BRAKE PEDAL AND STOP LIGHT SWITCH INSTALLATION

RECONFIRM DTC

INSPECT SKID CONTROL ECU (STP TERMINAL)

DTC C1422 Master Cylinder Pressure Sensor Zero Point High Malfunction


DESCRIPTION

The master cylinder pressure sensor is connected to the skid control ECU in the brake actuator assembly.

Yaris. Ncp93, 131.Brake Control Dynamic Control Systems.Anti-Lock Brake System (For Sedan). Dtc C1422 Master Cylinder Pressure Sensor Zero Point High Malfunction


DTC Code
DTC Detection Condition
Trouble Area
C1422
When the stop light switch is OFF, the PMC terminal voltage is more than 0.86 V for 5 seconds or more.
  1. Stop light switch
  2. Stop light switch circuit
  3. Master cylinder pressure sensor circuit
  4. Brake actuator assembly (Master cylinder pressure sensor)

WIRING DIAGRAM

Refer to DTC C1425 (YARIS_NCP93 RM000000XIE0EZX_02.html).

INSPECTION PROCEDURE

NOTICE:
  1. When replacing the brake actuator assembly, perform zero point calibration (YARIS_NCP93 RM000000XHR06QX.html).
  2. Inspect the fuses for circuits related to this system before performing the following inspection procedure.
HINT:
When C1425 is output together with C1422, inspect and repair the trouble areas indicated by C1425 first (YARIS_NCP93 RM000000XIE0EZX.html).
1.CHECK STOP LIGHT OPERATION

  1. Check that the stop lights come on when the brake pedal is depressed, and go off when the brake pedal is released.

    OK:
    Condition
    		Illumination Condition
    Brake pedal depressed
    		ON
    Brake pedal released
    		OFF


NG
INSPECT STOP LIGHT CIRCUIT (YARIS_NCP93 RM000003VC2007X.html)
OK


2.READ VALUE USING TECHSTREAM (STOP LIGHT SWITCH)

  1. Connect the Techstream to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the Techstream on.

  1. Enter the following menus: Chassis / ABS/VSC/TRAC / Data List.

    ABS/VSC/TRAC (Skid Control ECU)
    Tester Display
    		Measurement Item/Range
    		Normal Condition
    		Diagnostic Note
    Stop Light SW
    		Stop light switch / ON or OFF
    		ON: Brake pedal depressed
    OFF: Brake pedal released
    		-

  1. Check that the stop light condition observed on the Techstream changes according to brake pedal operation.

    OK:
    The Techstream displays ON or OFF according to brake pedal operation.


NG
Go to step 5
OK


3.CHECK BRAKE PEDAL AND STOP LIGHT SWITCH INSTALLATION

  1. Turn the ignition switch off.

  1. Check the brake pedal height and stop light switch installation (YARIS_NCP93 RM000001CES01OX.html).

    OK:
    The brake pedal height and stop light switch installation are normal.


NG
ADJUST BRAKE PEDAL OR STOP LIGHT SWITCH (YARIS_NCP93 RM000001CES01OX.html)
OK


4.RECONFIRM DTC

  1. Clear the DTCs (YARIS_NCP93 RM000000XHV0BQX.html).

  1. Start the engine.

  1. Drive the vehicle at a speed of 40 km/h (25 mph) or more and perform braking test (decelerate the vehicle by depressing the brake pedal).

  1. Check if the same DTC is recorded (YARIS_NCP93 RM000000XHV0BQX.html).

    Result
    Result
    		Proceed to
    DTC (C1422) is not output
    		A
    DTC (C1422) is output
    		B


B
REPLACE BRAKE ACTUATOR ASSEMBLY (YARIS_NCP93 RM000001BXP02FX.html)
A

CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) (YARIS_NCP93 RM000000XHS09YX.html)

5.INSPECT SKID CONTROL ECU (STP TERMINAL)


    Yaris. Ncp93, 131.Brake Control Dynamic Control Systems.Anti-Lock Brake System (For Sedan). Dtc C1422 Master Cylinder Pressure Sensor Zero Point High Malfunction

  1. Turn the ignition switch off.

    Text in Illustration
    *1
    		Front view of wire harness connector
    (to Skid Control ECU)

  1. Make sure that there is no looseness at the locking part and the connecting part of the connectors.

  1. Disconnect the skid control ECU connector.

  1. Measure the voltage according to the value(s) in the table below.

    Standard Voltage:
    Tester Connection
    		Switch Condition
    		Specified Condition
    A30-2 (STP) - Body ground
    		Stop light switch ON
    (Brake pedal depressed)
    		8 to 14 V
    A30-2 (STP) - Body ground
    		Stop light switch OFF
    (Brake pedal released)
    		Below 1.5 V


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (STP CIRCUIT)
OK

REPLACE BRAKE ACTUATOR ASSEMBLY (YARIS_NCP93 RM000001BXP02FX.html)